ThinkPad SL500 generating a lot of heat

My LenovoThinkPad SL500 ( 2746-4EG) generates a lot of heat – even grille above cooler burned and felt out. It makes no major difference what power plan I’m using (I’ve even tried to create my own power plan with only 20% of processor usage – it makes no difference) nor what operating system: Vista or XP – still generates a lot of heat. I’m neither playing games nor running “heavy” programs - only text editor and “Google Chrome”. Moreover, I’ve changed switchable graphics to energy saving mode – still no use.